SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e0610f3026ef922bbd2cdbdd35e23183ae1050c2559dc162f562c705e82d384c' 
  AND token = '6RmZGe9GKzNVMlPHfZMwUZzJoAwQvShGZ+fSHBWV12k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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