SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c73dc72215d0dd2637c05407f4cbbaf11cfe692464aade11007d5d4b782fa02d' 
  AND token = 'yJ4cQzL0b5VowJJYgpb/9TRKTa1LI07G+TcdTxbTBzM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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