SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0b5b66ad560283df50c30c6403d07befc16aa86439bbf1118b737644d946263f' 
  AND token = 'wVDH6671lR91WbuAXNd+WXGjBL2ENRskPrunO+DKk4M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00083

JSON explain

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