SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fedf2b40adb77be990c3500e67dfab3098e8e2c803d9cd87cb238347a4a18ca6' 
  AND token = 'PfOIFzMIT80at08W+8+a21ccJhcL6X+53iYs/ZpnoXo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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