SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'bfd656bd47202f1b6cabe5b9f5ec787a11c3aefafe6a5e676b59385b696f1781' 
  AND token = 'QQChLbr9xlKcpwrhl44wPQAiIo2lZPntOjLh2xpeTIQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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