SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ffccfa9861a43bd7ff4b76f46641e24d3b631840230f07ec5e87734996249d01' 
  AND token = 'sGPDRfKtMqX0fPQFIiH+syGB8KP/2lUIFtwbz5NtnaA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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