SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '656699b5eaf6b2998bcac1de7e04728397dd4afb3aa05a0e130e7e1334ce809d' 
  AND token = 'VpDwlOKun9bN8YbgCm6kihqfZ/cDYOqhmInPq+sR21o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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