SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3d1db1820868a5db2d64afd685b8b83b6b4b55fb4f2d95fbc428db69e53b08ca' 
  AND token = 'jlJnlbqv6O+Ku7aMrzwBGj/fbNHavU7G3bxzFsBXQHE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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