SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1973f4d6a160191f5749250f8d9d19c457a471f67276102876889059725e6c8d' 
  AND token = 'KeyeoSpgXXWrOgG/f4N0QnPGvRsFjDCsWdzJvQNDXbE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00011

JSON explain

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