SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1514a5808d90759623de0174846d3098d412acf9fca6ebf4810cfdfd6db81f88' 
  AND token = 'zC96mO8OIP07WGJqvHeYAnUkKwWUJHvbv3WoKoJM7H0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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