SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f1a4ae5b0fa26081daa7207314c31d93af562da1e50ae8d4b0e23690aa959578' 
  AND token = '+8IYl3M1PjN95fQVAMNvPsqUW8qX+kAB3GxzqsAp8Jk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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