SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa838e17ecab67497312efb1de626a527a099e763e30a85a03ee9f816be916e8' 
  AND token = 'V5nsMFi8PLCkLJBS9xEPlarak/GTeqJ3FboiwjenKUs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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