SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8ee15464913d5c5cc0040903fd76951cfbb80e4ec0d025fe451b9a07fee74ae9' 
  AND token = '7Joy0QRDcXCn6dORbi+sW/6PdcXFBaLpPCmuvrOis6o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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