SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0982db52f5b13cdec84c0845351a5155bbb765d697c232558adaed185e79bf8a' 
  AND token = 'eNq+vv9oI0AX+qHwk8yIozMT7cmw/6XQ91lpwfSbEgE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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