SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'acd43f632c3e0bff759ab0ce9fccd6bdb30810c2f04e1e6cffd1423238a67141' 
  AND token = 'YerTKkEQhQQwN7MCOgchoNliyp05egwflBklFEYl/Q8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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