SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f35f5523ee0333f5d30b81a66023dfb47d826db3ade93b13a7547174dc28f202' 
  AND token = 'VmGGsB7jgCYSEtfUb8XFNexK/ANXn2qb9b4A957g1SQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}