SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'e08ca1d1f5fb3a60eb90961144ac3c6e804e9837da4fb18bc32250214d0e61ff' 
  AND token = 'q7oS9knQLgtCDWZlVjaW83v1bQTcr2NQr+l7zBKlirg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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