SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '62a5601f94eb88c8ccd69bdb2e0d307c1d856f0d7ee66b2ea2628fc0c529563f' 
  AND token = 'DnWwKpwNZj7vc/mcosJJmBxDGSs6It5Pu12Jo45tn4M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}