SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed3817db4455aaf48f26e76a3ee38728930f0fd6e372bac80529f261e7d9cc8a' 
  AND token = 'riY6sk4u8Qhf86WbdU28ve71O68zQgKuHJM659JDwV4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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