SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d678a1fa090a5d3f298cac0fd4123374d3d34a4a1f290de98e9056a5663ba2c' 
  AND token = 'o2IQxdsH43skQYz+bYiqBcDMcv/im6ZR64WYM1HXorE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}