SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d4f5568b15ed687603cb56e963fccb4b53b85c5e19b725ba2994702cae0ea8a' 
  AND token = 'qo1YZD8Z/3Rb5mX+Y6t92YntpyKE8XfftnGPRgA1Gvg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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