SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '872bf6100b3515b301798e0c067b7a49a2c2f65af1849252f0c2a16a73a121b8' 
  AND token = 'KTNoTjPSps/xJfoFgMBC65uXCRHGz4NRXtY57EcW78g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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