SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba2124d286bebaedd8c65f5f34b19d5012f4415c7b380fdc5fb0db394f7eb90d' 
  AND token = '3rHkOoT2QuFyWBY0IYKDhtxOw59a2kt+8/YzliVyqXU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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