SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e375915add694b0496578424f0e4f6e691f1d54872c2f175ae0f9b11b451a722' 
  AND token = 'qv5W0QeqAs2YwPJcVWTI6sWYrU33s96zzSCPKOymjVA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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