SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3011b313d04aa8977f5d67b9fa9ed534056aa2149827c5594c20efbfa1bcf439' 
  AND token = 'MXJRFcXI8XuoJLIM2OVz1KEyaQeR1NKQwq3PSMQRZ78=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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