SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9276c0487e2102cd80589c39c3baa95a0743e591f4d512289cf942f84fefe2a4' 
  AND token = 'Rm7lwgwXUOM0KfXKBpEg9sDq5HGhC79DhUZjqSKL54U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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