SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '21f942af3d99f8507ed5b22c32c5dafd5ca0d218d6f0ab7255d62b475bcc2f5b' 
  AND token = 'pJTcHKlu1r7HodnphlE01oLubns6NxqmOHDWmckxKuM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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