SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5b04343efcd2b3117bf3eada1e467d906f813053bd4bcf54df8c44f851971187' 
  AND token = 'noG9ypyyCjXTvyZ/fp1ILeCnJzhR6EKwzGTJwSDYDAk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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