SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b56bd1eef73428f06706db5a5cb54f73be9271c45d628c4a6fd11dd610530221' 
  AND token = 'BQUQzQn1HaC62dewVgnMHvAfX1c+G4XgUx+a7fqfSNY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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