SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7b0c6479faeffffaeb5048cf6aee55100b17b91666f601d6d19dfa09ade59077' 
  AND token = 'wNGTXEokQ1k54zzv8fCJ8tATy0s/FlnS69lSHLOrBdY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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