SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '2529dd8f04533a551092d446b07f41395ee004c60f03df631545210a1eb18eaa' 
  AND token = 'Y5+6DGib8fZdrxeXWmyS7UCrMIYR7r/Dw3Nbxbdx9r4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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