Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3cb4c885d1a062b96e3ac4ef6590b15e1873d40992026fd89609a951649bf7fc' 
  AND token = 'Mpq1sHydxHjPLfD7YVJyfqTjj+8Jeg0dg0pyMf+KS6c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}