SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'e630309e47fd19653e4e09260af9c7a8178c244526c7bcd55d1d5c5383b0e9bc' 
  AND token = 'pFEElpJxMQGENJVX2PXAFPI/hIEB2OaMGbV4+o0+NDI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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