SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '63e0ec5d79f268ce2c1bb13a72551da98e202d3683173d52afc7b2d8a8c4f9f5' 
  AND token = 'H49LeW/hqz5qscVpk4LqZMXwYGvK9AmeW8DtB9ljT7Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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