SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60bb03bdf9e66335e8b2e34535c826fdaebe01099f21952d67b242d5a6f8d734' 
  AND token = 'UkjbnhosR6TJClti98Va6LLJG3alETRJZcdPdqK+P3M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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