SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8667d4b9e2f18a40ea478eabca76f5f0bd7723dfeb396060b87e36033f1156ff' 
  AND token = 'pWgf4QBOKWpSNC+FRllyzk441pyDCRY77Rq4w1QUFsY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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