SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b6c58f955ae277aad449338b94577399806c3f45c283ea7e657ae6f6937e5382' 
  AND token = 'dHNMnPrgUTukZ9MoNRvtcZniS1Nd+yqzp4KJWn5XmI8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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