SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '707a64ffc16a4770a6452f79c82e3998f793c430f23dd671c400964699a70919' 
  AND token = 'Nsh/BglpKc2/Bg/4aL74huV0Nzi+CFe5zeYweWOiuXY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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