SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '74cf3abe46cbb85e46f5a5ded8e351ddf6dc5757c10ac27672ede82636af1fbe' 
  AND token = 'G6jdhzSSxYOY9tugQEfy4RX1OH0o90sThe7Jyof3b2c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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