SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8d8b17d54ccfc9611fb9858f405473c0423231b17f39ca88ebfa5358c017a04a' 
  AND token = 'w8KWtDvfHAAlQgApZmzhMM53RS+phmDsZdiCURNs1TU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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