SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e1ae3f959ac5ec5f603cada2b1a2c2f56835dbb83aee7c45b55f909e3a68d774' 
  AND token = 'XD/4jqlnb9p1z2pZ1V1Crt1wBOx9OZQM1G/cDBXbeZI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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