SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3d5d61ce9218b44c8f1076c2ed8347eaea8679206d9e4f495cffd3ed0a522e6e' 
  AND token = 'chVAo/oaIdw7NGaRr4T/TtyU5cDCGelyYxMfGRnGX2M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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