SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ddfda3add7f22130919d5ba1a5b2057e24f41202001e6e3de774e6ad4545eff2' 
  AND token = 'RmFMQworDa81h3zYiPqMIEZot9fRSuQGDuWfMowMIWc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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