SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c23cd577efb4acf154a4399879109a11780b7dfedf546fc2d15f04af509e24fb' 
  AND token = 'XJn+GZJtsew1h1hAuCN/VM6YBLK/YYVjaGaAQ26mPpY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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