SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf686ab1b54e6e21f17e043e0542246e935800270f0647e2b2229e5410096656' 
  AND token = 'eWYHwT5RXiAL0KGZj5krwHmJCvsZ30Pc4z3JB2N5ykk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}