SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '05c300866138d9737f88406983a326ff68132c1fc1fa1fae22e0b4f29c606cb4' 
  AND token = 'espmuVCzn2aO7663dg1VFO19NenfcAqTVHQTIZNJKe4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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