SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c61dc0209e1e7889020da3ce75afa38267984caf0b4a5e1585d1bb6bc50de9bb' 
  AND token = 'GChEbo+942ELI9G9MwQUHEpX7yv0/4YotquMcqChXMA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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