SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4e063e957908f928889ac155af530f6aacd91a76ae9ca9fd87cf2e3631f481c6' 
  AND token = 'PmPZ17hs+gy2Z+Cj9SsgbaIwMYuWc58J6wMwKwDWDfQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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