SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '165c7aa353ee261b84746350cc4878889ee54b02bb6bb2e9a80184d7f1b486ea' 
  AND token = 'Sh5u1k23DTuHGIod/bYtzGszDCppPKLj6mUyP+ajiqo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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