SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'e2cdb43e8943cb72fa367ddf5a2371f3649d2f2d7c90df199555e0c0deb69bc8' 
  AND token = 'UYLJxfGwLgDwAvID6krGslc6cqDI6amhHGkuBtO1qCw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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