SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b3a0e6cc39083f7b67a0d48883510862ab05d952e0e148a728183c0438fcec56' 
  AND token = 'fgLwQmEkjgwJvsbTF8LG1J03z90EHc4aFo8fRZxyudc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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