SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1891298f9767acbaf0f3f0c061c8a50b1d65452556393152de22bf484411dbde' 
  AND token = 'YV6/g6AUGYJiHLtmHCzkU7dDjmVhyAUM8PUxRA6mCvU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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