SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '00d3b3eb82b40e8fdefc7fa348676b8b655ce6871a1292fb609d0c96b2edf3f1' 
  AND token = 'M+nxvfAimo336pZ4WTZTkGBzUyLtkv9cmzdJXlbOPxc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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