SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'fd7e97508086717b172f8d601487139fa95e5796c65ad5a467bccca7488ff0e9' 
  AND token = '095OKD14pFkTp1mmgKbmiE3FGOHXtuBE1XQpSDQV/lo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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