SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a097cab5c2d82829213f8af95f4b57dc8945fa633c79be4aa7f8905d2020aac3' 
  AND token = 'THzvkEUkV6FsCuOQjhqyi/1twWqjX+g2j0mXAXjiD7Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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